Single tool installation/removal of restraint cable with anti-rotation feature

Abstract

An anti-rotation duct restraint system and methods of using this system for connecting flexible ducts are described. The anti-rotation duct restraint system includes a flexible cable having a swaged cable end and a flattened threaded cable end, wherein the swaged cable end can be aligned with a though-hole in a first flange of a first flexible duct, and the flattened threaded cable end, along with a mating metal bushing, can be aligned with a through-hole in a second flange of a second flexible duct. The system also includes a nut, which can be threaded onto the flattened threaded cable end and secured using a single tool with one hand, for connecting the first flexible duct with the second flexible duct.

We claim: 
     
       1. A method of connecting flexible ducts using an anti-rotation duct restraint system, comprising:
 preparing a flexible cable having a swaged cable end coupled to the cable along an axis of the cable, and a flattened threaded cable end coupled to the cable along the axis of the cable; 
 aligning the swaged cable end with a through-hole in a first flange of a first flexible duct, and a washer, wherein the washer fits between the swaged cable end and the first flange of a first flexible duct; 
 aligning the flattened threaded cable end and a mating metal bushing with a through-hole in a second flange of a second flexible duct, wherein the mating metal bushing is adapted to fit over flattened threaded cable end, and wherein the flattened threaded cable end and mating metal bushing, together, fit into the second flange of the second flexible duct; and 
 securing the flattened threaded cable end to the second flange of the second flexible duct using a nut. 
 
     
     
       2. The method of  claim 1 , wherein the flexible cable comprises braided steel. 
     
     
       3. The method of  claim 1 , wherein the nut can be secured using a single tool with one hand. 
     
     
       4. The method of  claim 1 , wherein the nut is a lock nut. 
     
     
       5. The method of  claim 1 , wherein the length of the flexible cable allows for a desired space between the first flexible duct and the second flexible duct. 
     
     
       6. The method of  claim 1 , wherein the length of the flexible cable allows for a desired angle between the first flexible duct and the second flexible duct.